The Experts below are selected from a list of 222 Experts worldwide ranked by ideXlab platform
Bruce G. Lyeth - One of the best experts on this subject based on the ideXlab platform.
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icp monitoring in the rat comparison of monitoring in the ventricle brain parenchyma and cisterna magna
Journal of Neurotrauma, 1999Co-Authors: Marike Zwienenberg, Qin-zhi Gong, Lillian L. Lee, Robert F. Berman, Bruce G. LyethAbstract:Various methods of continuous intracranial pressure (ICP) monitoring during experimental procedures in the rat have been described. However, no systematic comparison of ICP monitoring in the ventricle, brain parenchyma, and cisterna magna has been reported. Since accurate and reliable ICP measurements are important in experimental models of traumatic brain injury, the present study was conducted to compare simultaneous ICP measurements from ventricular, cisterna magna, and intraparenchymal monitors during ICP changes. Subdural hematoma was produced by infusion of 0.3 ml of autologous blood into the subdural space over 6 min. The ventricular and the intraparenchymal Fiberoptic Catheter produced reliable and comparable pressure recordings, that did not statistically differ (p = 0.4), throughout the one hour monitoring time. In contrast, the cisterna magna Catheter was less reliable and produced significantly lower readings throughout the monitoring time (p<0.001). The intraparenchymal device produced greater cortical damage than the ventricular Catheter. In conclusion, ventricular ICP monitoring is the preferred method under these circumstances, since it is accurate and induces least brain damage.
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ICP Monitoring in the Rat: Comparison of Monitoring in the Ventricle, Brain Parenchyma, and Cisterna Magna
Journal of neurotrauma, 1999Co-Authors: Marike Zwienenberg, Qin-zhi Gong, Lillian L. Lee, Robert F. Berman, Bruce G. LyethAbstract:Various methods of continuous intracranial pressure (ICP) monitoring during experimental procedures in the rat have been described. However, no systematic comparison of ICP monitoring in the ventricle, brain parenchyma, and cisterna magna has been reported. Since accurate and reliable ICP measurements are important in experimental models of traumatic brain injury, the present study was conducted to compare simultaneous ICP measurements from ventricular, cisterna magna, and intraparenchymal monitors during ICP changes. Subdural hematoma was produced by infusion of 0.3 ml of autologous blood into the subdural space over 6 min. The ventricular and the intraparenchymal Fiberoptic Catheter produced reliable and comparable pressure recordings, that did not statistically differ (p = 0.4), throughout the one hour monitoring time. In contrast, the cisterna magna Catheter was less reliable and produced significantly lower readings throughout the monitoring time (p
R. Manoharan - One of the best experts on this subject based on the ideXlab platform.
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Side-viewing Fiberoptic Catheter for biospectroscopy applications
Lasers in Medical Science, 2004Co-Authors: C. J. Lima, S. Sathaiah, M. T. T. Pacheco, R. A. Zângaro, R. ManoharanAbstract:Utilization of Fiberoptic Catheters can turn the Raman and fluorescence spectroscopy systems into powerful bio-medical diagnostic probes. An in vivo bio-chemical diagnosis of some important organs like the esophagus, intestine, lung branches, artery, etc., can be possible by developing fiber-probes with good signal collection capabilities, a good flexibility to scan different spatial regions of the sample and less background signals generated in the probes themselves. An in vivo diagnosis of endoluminal inner walls utilizing front-viewing Catheters (FVC) is very difficult because the internal diameter of these organs do not allow (excitation and collection) flexibility to access the different spatial regions of the sample. In this work we have developed, different side-viewing Catheter (SVC) probes with a very small distal tip (semi sphere, φ~1.5 mm) and micro mirrors allow beam steering of the excitation and collected radiation at a 90 degree angle. Preliminary results of spectroscopic applications have been presented. Reflectance, fluorescence and Raman scattering measurements have been used to compare the efficiency of SVC with traditional FVC probes. The results demonstrate that the SVC probes not only exhibit more flexibility but also similar spectral characteristics and signal collection efficiencies in comparison with conventional FVC probes.
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Side-viewing Fiberoptic Catheter for biospectroscopy applications.
Lasers in medical science, 2004Co-Authors: C. J. Lima, S. Sathaiah, M. T. T. Pacheco, R. A. Zângaro, R. ManoharanAbstract:Utilization of Fiberoptic Catheters can turn the Raman and fluorescence spectroscopy systems into powerful bio-medical diagnostic probes. An in vivo bio-chemical diagnosis of some important organs like the esophagus, intestine, lung branches, artery, etc., can be possible by developing fiber-probes with good signal collection capabilities, a good flexibility to scan different spatial regions of the sample and less background signals generated in the probes themselves. An in vivo diagnosis of endoluminal inner walls utilizing front-viewing Catheters (FVC) is very difficult because the internal diameter of these organs do not allow (excitation and collection) flexibility to access the different spatial regions of the sample. In this work we have developed, different side-viewing Catheter (SVC) probes with a very small distal tip (semi sphere, phi approximately 1.5 mm) and micro mirrors allow beam steering of the excitation and collected radiation at a 90 degree angle. Preliminary results of spectroscopic applications have been presented. Reflectance, fluorescence and Raman scattering measurements have been used to compare the efficiency of SVC with traditional FVC probes. The results demonstrate that the SVC probes not only exhibit more flexibility but also similar spectral characteristics and signal collection efficiencies in comparison with conventional FVC probes.
Carlos E. Blanco - One of the best experts on this subject based on the ideXlab platform.
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Mixed Venous Oxygen Saturation and Biochemical Parameters of Hypoxia during Progressive Hypoxemia in 10- to 14-Day-Old Piglets
Pediatric Research, 1997Co-Authors: Mark A. H. B. M. Van Der Hoeven, Wiel J Maertzdorf, Carlos E. BlancoAbstract:In this study we wanted to assess the relationship between mixed venous oxygen saturation (Svo_2) and tissue oxygenation. For that, we compared the values of Svo_2 with oxygen delivery (Do_2), oxygen consumption (Vo_2), and markers of tissue hypoxia such as lactate and pyruvate during progressive hypoxemia. Eight 10-14-d-old piglets were anesthetized, tracheotomized, intubated, and ventilated. A Fiberoptic Catheter was placed in the carotid artery to monitor arterial oxygen saturation(Sao_2). A thoracotomy was performed, and a Fiberoptic Catheter was placed in the pulmonary artery to monitor Svo_2. A transit time ultrasound flow probe was positioned around the ascending aorta to measure aorta flow. Progressive graded hypoxemia was induced by decreasing fractional inspiratory oxygen concentration (Fio_2) from 1.0 to 0.30, 0.21, 0.15, and 0.10. After each Fio_2 interval blood samples were taken for blood gases, lactate, and pyruvate. Do_2 and Vo_2 were calculated. Svo_2 decreased similarly to Sao_2. A value of Svo_2 of more than 40% excluded oxygen restricted metabolism. When Do_2 decreased below a critical range (8.4-12.8 mL/kg·min), Svo_2 decreased below 15%, and lactate and the lactate/pyruvate ratio increased. We conclude 1 ) that baseline Svo_2 values excluded oxygen-restricted metabolism, 2 ) that Svo_2 values between 15 and 40% were not a marker for oxygen-restricted metabolism, and 3 ) that Svo_2 values below 15% were associated with oxygen-restricted metabolism. Reduced Svo_2 values must be interpreted as a change of the factors that determine the balance between Do_2 and Vo_2 and as a warning that, with further reduction of Svo_2, oxygen restricted metabolism can develop.
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Central venous oxygen saturation (ScvO 2 ) at different ranges of arterial oxygenation in newborn infants with respiratory insufficiency.† 1086
Pediatric Research, 1997Co-Authors: Mark A. H. B. M. Van Der Hoeven, Wiel J Maertzdorf, Carlos E. BlancoAbstract:Objective: To describe the ScvO2 levels at the lower (86-90%) and higher (91 - 96%) end of the currently recommended range of pulseoximetry (SpO2) in newborn infants with respiratory insufficiency. Design: a prospective observational study. Patients: 10 newborn infants (birthweight: 720 - 3400 grams) suffering from RDS and treated with mechanical ventilation and oxygen administration. Methods: SpO2 and ScvO2 were measured continuously by pulseoximetry, and by a Fiberoptic Catheter inserted into the right atrium via the umbilical vein, respectively. Measurements and Results: SpO2, ScvO2 were registered and venous admixture (Ven Adm) (100- SpO2)/(100 - ScvO2) was calculated every 15 minutes. For each patient the mean values of SpO2, ScvO2 and Ven Adm were calculated for both levels of oxygenation (table). In all patients ScvO2 was significantly reduced and Ven Adm was significantly increased at the lower range of oxygenation (p < 0.05; unpaired Student's T test).
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Venous Oxygen Saturation (SvO2) During Alveolar Hypoxia and Anemic Hypoxia. 115
Pediatric Research, 1996Co-Authors: Mark A. H. B. M. Van Der Hoeven, Wiel J Maertzdorf, Carlos E. BlancoAbstract:Background: We studied SvO2 and markers of tissue hypoxia to assess the value of SvO2 during two types of hypoxia. Subjects: Two groups of ventilated neonatal piglets. Intervention: We induced alveolar hypoxia by giving FiO2: 0.1 in one group (ALV) and anemic hypoxia by exchanging blood with plasma in the other group (ANEM). SvO2 was measured by a Fiberoptic Catheter (Oximetrix, Abbott Lab). Aorta flow (Qt), arterial and venous bloodgases, hemoglobin and lactate were measured. O2 delivery (DO2), percent change O2 consumption (perc.ch VO2) and percent change lactate(perc.ch LAC) were calculated. Mann-Whitney U test was applied. Results: *: p = 0.002; Table
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ACCURACY OF CENTRAL VENOUS OXYGEN SATURATION (cSvO2) MEASUREMENTS THROUGH A Fiberoptic Catheter
Pediatric Research, 1992Co-Authors: Mark A. H. B. M. Van Der Hoeven, Pieter L.j. Degraeuwe, Wiel J Maertzdorf, Carlos E. BlancoAbstract:ACCURACY OF CENTRAL VENOUS OXYGEN SATURATION (cSvO2) MEASUREMENTS THROUGH A Fiberoptic Catheter
Marike Zwienenberg - One of the best experts on this subject based on the ideXlab platform.
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icp monitoring in the rat comparison of monitoring in the ventricle brain parenchyma and cisterna magna
Journal of Neurotrauma, 1999Co-Authors: Marike Zwienenberg, Qin-zhi Gong, Lillian L. Lee, Robert F. Berman, Bruce G. LyethAbstract:Various methods of continuous intracranial pressure (ICP) monitoring during experimental procedures in the rat have been described. However, no systematic comparison of ICP monitoring in the ventricle, brain parenchyma, and cisterna magna has been reported. Since accurate and reliable ICP measurements are important in experimental models of traumatic brain injury, the present study was conducted to compare simultaneous ICP measurements from ventricular, cisterna magna, and intraparenchymal monitors during ICP changes. Subdural hematoma was produced by infusion of 0.3 ml of autologous blood into the subdural space over 6 min. The ventricular and the intraparenchymal Fiberoptic Catheter produced reliable and comparable pressure recordings, that did not statistically differ (p = 0.4), throughout the one hour monitoring time. In contrast, the cisterna magna Catheter was less reliable and produced significantly lower readings throughout the monitoring time (p<0.001). The intraparenchymal device produced greater cortical damage than the ventricular Catheter. In conclusion, ventricular ICP monitoring is the preferred method under these circumstances, since it is accurate and induces least brain damage.
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ICP Monitoring in the Rat: Comparison of Monitoring in the Ventricle, Brain Parenchyma, and Cisterna Magna
Journal of neurotrauma, 1999Co-Authors: Marike Zwienenberg, Qin-zhi Gong, Lillian L. Lee, Robert F. Berman, Bruce G. LyethAbstract:Various methods of continuous intracranial pressure (ICP) monitoring during experimental procedures in the rat have been described. However, no systematic comparison of ICP monitoring in the ventricle, brain parenchyma, and cisterna magna has been reported. Since accurate and reliable ICP measurements are important in experimental models of traumatic brain injury, the present study was conducted to compare simultaneous ICP measurements from ventricular, cisterna magna, and intraparenchymal monitors during ICP changes. Subdural hematoma was produced by infusion of 0.3 ml of autologous blood into the subdural space over 6 min. The ventricular and the intraparenchymal Fiberoptic Catheter produced reliable and comparable pressure recordings, that did not statistically differ (p = 0.4), throughout the one hour monitoring time. In contrast, the cisterna magna Catheter was less reliable and produced significantly lower readings throughout the monitoring time (p
C. J. Lima - One of the best experts on this subject based on the ideXlab platform.
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Side-viewing Fiberoptic Catheter for biospectroscopy applications
Lasers in Medical Science, 2004Co-Authors: C. J. Lima, S. Sathaiah, M. T. T. Pacheco, R. A. Zângaro, R. ManoharanAbstract:Utilization of Fiberoptic Catheters can turn the Raman and fluorescence spectroscopy systems into powerful bio-medical diagnostic probes. An in vivo bio-chemical diagnosis of some important organs like the esophagus, intestine, lung branches, artery, etc., can be possible by developing fiber-probes with good signal collection capabilities, a good flexibility to scan different spatial regions of the sample and less background signals generated in the probes themselves. An in vivo diagnosis of endoluminal inner walls utilizing front-viewing Catheters (FVC) is very difficult because the internal diameter of these organs do not allow (excitation and collection) flexibility to access the different spatial regions of the sample. In this work we have developed, different side-viewing Catheter (SVC) probes with a very small distal tip (semi sphere, φ~1.5 mm) and micro mirrors allow beam steering of the excitation and collected radiation at a 90 degree angle. Preliminary results of spectroscopic applications have been presented. Reflectance, fluorescence and Raman scattering measurements have been used to compare the efficiency of SVC with traditional FVC probes. The results demonstrate that the SVC probes not only exhibit more flexibility but also similar spectral characteristics and signal collection efficiencies in comparison with conventional FVC probes.
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Side-viewing Fiberoptic Catheter for biospectroscopy applications.
Lasers in medical science, 2004Co-Authors: C. J. Lima, S. Sathaiah, M. T. T. Pacheco, R. A. Zângaro, R. ManoharanAbstract:Utilization of Fiberoptic Catheters can turn the Raman and fluorescence spectroscopy systems into powerful bio-medical diagnostic probes. An in vivo bio-chemical diagnosis of some important organs like the esophagus, intestine, lung branches, artery, etc., can be possible by developing fiber-probes with good signal collection capabilities, a good flexibility to scan different spatial regions of the sample and less background signals generated in the probes themselves. An in vivo diagnosis of endoluminal inner walls utilizing front-viewing Catheters (FVC) is very difficult because the internal diameter of these organs do not allow (excitation and collection) flexibility to access the different spatial regions of the sample. In this work we have developed, different side-viewing Catheter (SVC) probes with a very small distal tip (semi sphere, phi approximately 1.5 mm) and micro mirrors allow beam steering of the excitation and collected radiation at a 90 degree angle. Preliminary results of spectroscopic applications have been presented. Reflectance, fluorescence and Raman scattering measurements have been used to compare the efficiency of SVC with traditional FVC probes. The results demonstrate that the SVC probes not only exhibit more flexibility but also similar spectral characteristics and signal collection efficiencies in comparison with conventional FVC probes.